1. Field of the invention
This invention relates to a combination structure of an electronic equipment including an electrical control circuit portion and a power circuit portion for providing electric power.
2. Description of the Related Art
Electronic control units (ECUs), each provided in a combined manner as a unit in accordance with the function of an object to be controlled, have heretofore been mounted on a vehicle. Each of the ECUs includes a control circuit portion (including a microcomputer or the like) for effecting a logical control operation, and a power circuit portion for controlling power to be fed to an exterior.
FIG. 15 roughly shows a combination structure of a conventional electronic control unit 1. Main portions of the electronic control unit 1 are contained in a connector-incorporating resin casing 2. A control connector 3 and power connectors 4 and 5 are provided in a gathered manner on one side surface of the connector-incorporating resin casing 2. With this construction, the connection to the electronic control unit 1 can be effected only from one direction. A plurality of power parts 6 and 7 are mounted within the connector-incorporating resin casing 2, and also connection terminals 8 and 9 are provided within the connector-incorporating resin casing 2. The connection terminals 8 and 9 are adapted to be electrically connected to a control board 10. The control board 10 is attached to the upper side of connector-incorporating resin casing 2, and has through holes 11 and 12 adapted to be electrically connected to the connection terminals 9 and the connection terminals 8, respectively. A plurality of control parts 13, 14 and 15 are mounted on the control board 10. A lid 20 is fitted on the casing 2 to cover the control board 10. A heatsink 21 is attached to the bottom of the connect-incorporating casing 2. A waterproof packing 22 is provided at a region of connection between the lid 20 and the connector-incorporating casing 2, and a waterproof packing 23 is provided at a region of connection between the connector-incorporating casing 2 and the heatsink 21.
In the combination structure shown in FIG. 15, the control board 10 is fixedly secured to the connect-incorporating casing 2 having the power parts 7 and 8 and so on mounted therein, and the control connector 3 and the power connectors 4 and 5 are formed integrally with the connector-incorporating casing 2. Therefore, the connector-incorporating casing 2 has a complicated construction, and can not be easily formed, and besides the assembling operation is difficult. JP-A-7-297561 discloses the conventional art concerning a box member of an electronic equipment in which a control circuit portion, a drive circuit portion and a power circuit portion are provided separately from one another in a manner to provide separate spaces. Radiating fins are mounted on the power circuit portion so as to prevent the temperature of the box member of the electronic equipment from rising. The circuit portions, which are different in signal level from one another, are separated from one another so as to reduce the rate of occurrence of malfunction due to noises. Signal input-output elements of the drive circuit portion are disposed near to signal input-output elements of the power circuit portion, and the two circuit portions are electrically connected directly to each other. However, the electrical connection between the drive circuit portion and the control circuit portion is made by a pair of connectors. Therefore, this structure can be regarded as being of the type in which the control circuit portion and the power circuit portion, including the drive circuit portion, are combined together.
In the combination structure shown in FIG. 15, the power connectors 4 and 5 and the control connector 3 are formed integrally with the connector-incorporating resin casing 2, and therefore the connector-incorporating resin casing 2 has a complicated construction, and can not be easily formed, and besides the assembling operation is difficult. Particularly when the connectors are increased in size and when the number of memories increases, it is difficult to provide the connectors on the same side surface of the connector-incorporating resin casing 2. The electronic control unit 1 is electrically connected to the exterior via wire harnesses, and when all of the connectors are not provided on the same side surface, the wire harnesses can not be easily arranged and installed, so that an installation space is increased. And besides, the packing 22 is used between the lid 20 and the casing 2, and also the packing 23 is used between the casing 2 and the heatsink 21, and this increases the production cost.
In the structure disclosed in JP-A-7-297561, the control circuit portion is connected to the drive circuit portion and the power,circuit portion by the connectors, and therefore parts of these circuit portions need to be electrically connected to the connectors, and the amount of wires, used in each circuit portion, increases.
Conventionally, a large amount of heat is generated at bus bars which are near to connector pins of the connectors 4 and 5 attached to the power circuit portion of the electronic control unit 1 and which are connected to the connection terminals 8 and 9, in which a large electric current flows. The heat generated near to the connector pins or at the bus bar portion is radiated by the heatsink 21 fixed to the bottom surface of the connector-incorporating resin casing 2. The increase of the heatsink 21 in size can improve the heat radiation efficiency so that the control circuit portion is not adversely affected by heat. However, the increase of the heatsink 21 in size results in the increase of the total size of the electronic control unit 1, which makes the size reduction of the electronic control unit 1 difficult. Moreover, use of the large heatsink increases the manufacturing cost of the electronic control unit 1, which is inconvenient for the maker.
It is an object of this invention to provide a combination structure of an electronic equipment in which a control circuit portion and a power circuit portion are separated from each other so that the control circuit portion will be less affected by heat, generated by the power circuit portion, and will be less affected by noises, and besides an assembling operation can be effected easily.
According to the present invention, there is provided a combination structure of an electronic equipment wherein the electronic equipment comprises a control portion and a power portion which are separate from each other, and the control portion and the power portion are combined together;
wherein the control portion includes a control casing, and a plurality of control parts are provided within the control casing, and a plurality of control-side terminals, electrically connected to the respective control parts, are provided upright in a concentrated manner at a predetermined portion, and a hollow portion is provided within the control casing;
wherein the power portion includes a power casing, and a plurality of power parts are provided within the power casing, and a plurality of power-side terminals, electrically connected to the respective power parts, are provided upright in a concentrated manner at a predetermined portion; and
wherein when the control portion and the power portion are combined together, the plurality of power-side terminals extend into the hollow portion of the control portion, and can contact the plurality of control-side terminals, respectively.
In the invention, the electronic equipment comprises the separate control and power portions which are combined together. The plurality of control parts are provided within the control casing of the control portion, and the plurality of control-side terminals, electrically connected to the respective control parts, are provided upright in a concentrated manner at the predetermined portion, and the hollow portion is provided within the control casing. The plurality of power parts are provided within the power casing of the power portion, and the plurality of power-side terminals, electrically connected to the respective power parts, are provided upright in a concentrated manner at the predetermined portion. When the control portion and the power portion are combined together, the plurality of power-side terminals extend into the hollow portion of the control portion, and can contact the plurality of control-side terminals, respectively. With this construction, merely by stacking the control portion and power portion together, the electrical connection can be effected. The control portion and the power portion are provided separately from each other, and therefore as compared with an integral construction, the control portion is less affected by heat from the power portion, and is less affected by noises, so that a stable operation can be effected.
In the invention, a control board is provided at the control portion, and a plurality of connection terminals, electrically connected to the plurality of control parts, are provided upright on the control board;
the control casing has a wall dividing an internal space of the control casing into a first hollow portion and a second hollow portion;
a plurality of relay connection terminals, forming the plurality of control-side terminals, are formed on the wall;
the plurality of power-side terminals can extend into the first hollow portion;
the control board can be received within the second hollow portion;
when the control board is received within the second hollow portion, the plurality of upright connection terminals can contact one ends of the plurality of relay connection terminals, respectively; and
when the control portion is stacked on the power portion, the plurality of power-side terminals extend into the first hollow portion, and can contact the other ends of the relay connection terminals, respectively.
In the invention, the internal space of the control casing is divided into the first hollow portion and the second hollow portion by the wall. The control board, on which the plurality of connection terminals, electrically connected to the plurality of control parts, are provided upright, is received within the second hollow portion. When the control board is received within the second hollow portion, the plurality of connection terminals, provided upright on the control board, contact one ends of the plurality of relay connection terminals, respectively. When the control portion is stacked on the power portion, the plurality of power-side terminals extend into the first hollow portion, and contact the other ends of the relay connection terminals, respectively. The control board and the power portion can be connected together through the relay connection terminals, and therefore even if the connection terminals are randomly provided upright in accordance with the arrangement of the control parts on the control board, the connection terminals can be connected to the relay connection terminals in a concentrated manner, and the control portion-side terminals are disposed very close to the respective power portion-side terminals, and the electrical connection therebetween can be easily effected when the control portion and the power portion are combined together.
In the invention, a plurality of connection terminals, electrically connected to the plurality of power parts, are provided upright at the power portion;
there is provided an intermediate layer for mounting on the power portion, and a plurality of power portion connection terminals are provided upright on the intermediate layer, and correspond in position to the plurality of connection terminals within the power portion, and insertion holes are formed through the intermediate layer, and are disposed adjacent to the power portion connection terminals, respectively, and the plurality of power-side terminals, electrically connected respectively to the plurality of power portion connection terminals, are formed upright in a concentrated manner on a predetermined portion of the intermediate layer; and
when the intermediate layer is mounted on the power portion, the plurality of connection terminals extend respectively through the insertion holes, and can contact the plurality of power portion connection terminals, respectively.
In the invention, the plurality of connection terminals, electrically connected to the plurality of power parts, are provided upright at the power portion, and the plurality of power portion connection terminals are provided upright on the intermediate layer, and correspond in position to the plurality of connection terminals within the power portion, and the insertion holes are formed through the intermediate layer, and are disposed adjacent to the power portion connection terminals, respectively, and the plurality of power-side terminals, electrically connected respectively to the plurality of power portion connection terminals, are formed upright in a concentrated manner on the predetermined portion of the intermediate layer. The plurality of connection terminals of the power portion extend respectively through the insertion holes in the intermediate layer, and contact the plurality of power portion connection terminals, respectively. Even if the connection terminals are randomly provided upright in accordance with the arrangement of the power parts within the power casing, these connection terminals can be contacted with the respective power portion connection terminals on the intermediate layer, and can be connected to the power-side terminals in a concentrated manner in the intermediate layer. The control portion-side terminals are disposed very close to the power portion-side terminals, and the electrical connection therebetween can be easily effected when the control portion and the power portion are combined together.
In the invention, insertion holes are formed in the power casing of the power portion, and each terminal of each of the power parts can project through the corresponding insertion hole in a direction away from that side of the power casing to be combined with the control portion, and the power casing has bus bars each exposed to the corresponding insertion hole and projecting in the direction away from the combination side of the power casing; and
when each of the power parts is mounted on the power casing, each terminal of the power part projects through the corresponding insertion hole in the direction away from the combination side of the power casing, and can contact the corresponding bus bar.
In the invention, the terminals of the power parts are contacted with the respective bus bars at the power portion, and the control portion is combined with that side of the power portion facing away from this connection portion, and the power portion and the control portion are joined together. Therefore, the joining of the terminals of the power parts to the respective bus bars and the electrical connection between the control portion and the power portion can be easily effected separately from each other.
In the invention, the connection between the plurality of power-side terminals and the plurality of control-side terminals, the connection between the plurality of connection terminals, provided upright on the control board, and one ends of the plurality of relay connection terminals, the connection between the plurality of power-side terminals and the other ends of the plurality of relay connection terminals, the connection between the plurality of connection terminals, provided upright at the power portion, and the plurality of power portion connection terminals, and the connection between the terminals of the power parts and the bus bars are effected by resistance welding.
In the invention, the plurality of power-side terminals can be disposed to contact the plurality of control-side terminals, and the plurality of connection terminals, provided upright on the control board, can be disposed to contact one ends of the plurality of relay connection terminals, and the plurality of power-side terminals can be disposed to contact the other ends of the plurality of relay connection terminals, and the plurality of connection terminals, provided upright at the power portion, can be disposed to contact the plurality of power portion connection terminals, and the terminals of the power parts can be disposed to contact the bus bars. Therefore, these mating portions, while held in contact with each other, are joined together by resistance welding, and therefore the positive electrical connection can be effected easily.
In the invention, welding portions which can be joined together by ultrasonic welding, or welding portions, which can be jointed together by vibration welding, are formed respectively at those portions of the power portion and the control portion which are to be combined together.
In the invention, the welding portions which can be joined together by ultrasonic welding, or the welding portions, which can be jointed together by vibration welding, are formed respectively at those portions of the power portion and the control portion which are to be combined together. Therefore, the waterproof effect and the joining can both be effected without the use of a packing or the like.
In the invention, after the control board is received in the second hollow portion of the control portion, a resin layer is formed by resin potting in such a manner that the control board is sealed in the resin layer.
In the invention, the control board is received in the second hollow portion of the control casing, and then the resin layer is formed by resin potting in such a manner that the control board is sealed in the resin layer. Therefore, the electrical connection portions in the control board are prevented from being exposed, thereby enhancing the reliability.
In the invention, parts are mounted on the intermediate layer.
In the invention, the parts are also mounted on the intermediate layer, and therefore for example, the power parts are mounted on the intermediate layer so that the degree of freedom of arrangement of the parts in the power portion can be increased. For example, when a drive circuit for driving a power control element at the power portion in response to a signal from the control portion is provided on the intermediate layer, signals in the electronic equipment flow generally from the control portion to the power portion, so that the reliability can be enhanced.
In the invention, a heatsink for radiating heat from the power portion is mounted on the power portion;
a recess for receiving the terminals of the power parts and the bus bars is formed in the heatsink; and
a resin is filled in the recess by resin potting, so that the terminals of the power parts and the bus bars are sealed in the resin.
In the invention, the recess for receiving the terminals of the power parts and the bus bars is formed in the heatsink mounted on the power portion so as to radiate heat from the power port on, and the resin is filled in the recess by resin potting, so that the terminals of the power parts and the bus bars are sealed in the resin. Therefore, the reliability of the connection portions is enhanced, and besides heat can be efficiently radiated from the power portion, thereby reducing adverse effects of the heat on the electronic equipment.
In the invention, a heatsink is disposed under the power portion for radiating heat from the power portion, in which the heatsink defines a recess filled with the resinl. In the heat sink, at least one of the plurality of bus bars elongates above the recess and are inserted into the recess.
In the invention, the at least one of the plurality of bus bars may comprises a first bus bar elongating above the recess, and a second bus bar inserted into the recess, the second bus bar connected to the first bus bar.
In the invention, the at least one of the plurality of bus bars may be inserted into the recess and fold back upwardly.
In the invention, a part of at least one of the plurality of bus bars is disposed along with an inner side surface of the power casing.
In the invention, the plurality of bus bars are embedded in a synthetic resin layer in the power casing, and a part of at least one of the plurality of bus bars is exposed out of the synthetic resin layer.